Porous rigid resins and process of preparation

ABSTRACT

Porous, rigid resin particles are prepared having a predetermined particle size distribution, surface area and porosity by polymerizing in the pores of porous inorganic template particles a reaction mixture comprising monovinyl monomers, polyvinyl crosslinking monomers and a polymerization initiator in a liquid medium in which the monomers and initiator are phase separable and extractable therefrom into the pores of the template particles. The extracted mixture is polymerized in the pores of the template particles, and the template particles are removed without destruction of the polymerizate. The isolated polymerizate mirrors the characteristics of the template particles. The surface of the polymerizate may be modified in various ways to contain desired functionality. The particles of the invention are useful in chromatography, adsorption, ion exchange, and in catalysis.

This is a division of application Ser. No. 249,762, filed Sept. 26,1988, now allowed.

TECHNICAL FIELD

This invention relates to resins useful in chromatographic analysis andpreparative high performance liquid chromatography, and as polymericreagents including adsorbents and polymeric catalysts. The inventionfurther relates to processes for preparing and modifying the surfacecharacteristics of the resins, based upon a templating technique.

BACKGROUND OF THE INVENTION

The ability to reproducibly synthesize porous, rigid resins which arechemically stable to organic solvents over a wide pH range and whichhave a desired shape, size, porosity and surface area, has substantialcommercial importance. The value is further enhanced if the resins canbe modified to provide functionality suitable for ion exchange or otherreactivity. One such technique is based upon use of inorganic particleshaving a desired size, surface area and porosity to extract the reactivecomponents from a reaction mixture placed in contact with the inorganicparticles, followed by polymerization of reactants within the pores ofthe inorganic particles and removal of the inorganic particles withoutdestruction of the polymerizate. Theoretically, at least, the isolatedpolymerizate should mirror the size, surface area and porosity of theinorganic particles.

U.S. Pat. No. 4,263,268 to Knox and Gilbert describes a method ofpreparing porous carbon by depositing a polymerizable mixture in thepores of a porous inorganic template such as silica gel, polymerizingthe mixture, pyrolyzing the resulting polymer, and dissolving thetemplate material. This work is also reported in LC/GC 5 No. 2. (1987)165.

U.S.S.R. Invention Description With Authors Certificate No. 208942,published Jan. 17, 1968, describes a method of preparing macroporous ionexchange resins by copolymerizing styrene with divinyl benzene in aporous matrix such as silica gel having a surface area of 20-300 m² /g,an average pore diameter of 100-150 Angstroms, and a particle size of1-2 mm. The resulting swollen particles are transferred to a saturatedCaCl₂ solution and the temperature raised to 70° C. for 4-5 hours. Thesilica gel particles containing the copolymer are then combined withdichloroethane and heated for 30 minutes at 70° C. The dichloroethane iswashed out with ethyl ether and the resulting beads are allowed to stand2-3 hours in an NaOH solution. The alkali is washed off the beads withdistilled water and the beads are dried. The porosity of the resultingcopolymer beads, determined by acetone, is 0.5 cm³ /g, and the specificarea measured by BET is 150-200 m² /g. The beads may be ion exchangefunctionalized by sulfonation in the usual manner.

The process of the U.S.S.R. publication appears to be a bulkcopolymerization, the dichloroethane operating as an inert solvent andprecipitant to dissolve the monomers but not the copolymer. The largeproportion of monomers relative to the silica gel suggests thatagglomeration is taking place. Moreover, the silica gel appears to be aconventional hydrophilic material and thus is incompatible with thehydrophobic monomers. Still further, the very large particle size of thesilica gel indicates that the copolymer particles, once separated fromthe silica gel by treatment with the caustic, could not be used forhigh-performance chromatography. In any event, the pore volume of thesilica gel is not given and therefore the efficiency of thecopolymerization and the extent to which the copolymer mirrors theparticle size and pore diameter of the silica gel cannot be determined.

SUMMARY OF THE INVENTION

It has now been found, in accordance with one aspect of the invention,that porous rigid resin particles can be prepared with little or no lossof product by agglomeration and having particle-size distribution,surface area and porosity of virtually any predetermined values, bypolymerizing in the pores of porous inorganic template particles areaction mixture comprising monoethylenically unsaturated monomers,polyethylenically unsaturated crosslinking monomers and a polymerizationinitiator, in a liquid medium in which the monomers and initiator arephase separable and extractable therefrom into the pores of the templateparticles. Following the copolymerization, the template particles areremoved without destroying the copolymer, with the result that theisolated copolymer particles mirror the size, surface area and porosityof the template particles.

In another aspect of the invention, the volume of the reaction mixtureis approximately equal to the pore volume of the inorganic templateparticles, to further reduce agglomeration and to increase the yield ofdesirable product.

In other aspects of the invention, desired functionality is provided onthe surface of the copolymer resin particles in several ways, including(1) absorption onto the surface of the template particles of anethylenically unsaturated compound carrying additional desiredfunctionality, followed by bonding of the compound to the copolymerduring polymerization and removal of the template particles; (2)providing in the reaction mixture a compound carrying the desiredfunctionality, the template particles being modified with functionalgroups capable of associating with the functionality of the compound,whereby the functional groups are populated on the surface of thecopolymer particles; and (3) by chemically bonding an ethylenicallyunsaturated compound containing the desired functionality onto thetemplate particles, the functionality then being transferred to thecopolymer, followed by removal of the template particles.

The invention is applicable to copolymers based upon hydrophobicmonomers, hydrophilic monomers, and to monomers carrying otherfunctionality, to yield porous, rigid resins which mirror the size,surface area, and porosity of the template particles. The templateparticles thereby predetermine the fields of application of thecopolymer particles, with modification of the particles as required,such fields including chromatographic analysis and preparativetechniques, adsorbents, catalytic materials, polymeric reagents, and awide variety of ion exchange resins. Because the controlling factor isthe character of the template particles, particulate resins can beproduced having specific particle properties selected within a widerange of particle size, porosity and pore size, thus avoiding theadditional step and associated cost of classifying resinous particulateproducts according to desired characteristics. However, in cases wherefurther classification is still desired, the high density of thesilica-polymer intermediate makes air-classification practical even forparticles in the 2-10 um range.

DETAILED DESCRIPTION

The invention is applicable to any copolymers prepared from mixtures ofmonoethylenically and polyethylenically unsaturated monomers which arecopolymerizable in the liquid state. The monoethylenically unsaturatedmonomers include vinyl monomers such as vinylaromatic and vinylaliphaticmonomers. Representative of vinyl monomers are aromatic monomers such asstyrene and substituted styrenes, including methylstyrenes,ethylstyrenes, the various dialkyl-styrenes, chloromethylstyrene,isopropenyltoluene, vinylnaphthalene, vinylanisole, vinylxylene, andvinylpyridine, vinyl acetate, vinyl propionate, and any mixture thereof,and acrylic monomers, including the alkyl (C₁ -C₈) esters of acrylic ormethacrylic acid, such as methyl acrylate, ethyl acrylate, propylacrylate, isopropyl acrylate, butyl acrylate, tert-butyl acrylate andethylhexyl acrylate, and others, including cyclohexyl acrylate,isobornyl acrylate, benzyl acrylate, phenyl acrylate, alkyl (C₁-C₉)phenyl acrylate, ethoxymethyl acrylate, ethoxyethyl acrylate,ethoxypropyl acrylate, propoxymethyl acrylate, propoxyethyl acrylate,ethoxyphenyl acrylate, ethoxybenzyl acrylate, the correspondingmethacrylic acid esters, and other monomers such asN-2-(N-ethylperfluorooctanesulfonamide)ethyl methacrylate. The preferredacrylic esters are the lower aliphatic esters of acrylic acid in whichthe ester group contains 1-5 carbon atoms, such as ethyl acrylate andthe various butyl acrylates.

Suitable polyethylenically unsaturated crosslinking monomers includedivinylbenzene, divinylpyridine, divinyltoluenes, divinylnaphthalenes,ethylene glycol dimethacrylate, glycidyl methacrylate, triallylisocyanurate, pentaerythritol trimethacrylate, divinylxylene,divinylethylbenzene, divinylsulfone, divinylketone, divinylsulfide,trivinylbenzene, trivinylnaphthalene, trimethylolpropanetrimethacrylate, polyvinylanthracenes and the polyvinyl ethers ofglycol, gylcerol, pentaerythritol and resorcinol. Particularly preferredcrosslinking monomers are the polyvinylaromatic hydrocarbons such asdivinylbenzene, the glycol dimethacrylates such as ethylene glycoldimethacrylate, and the polyvinyl ethers of polyhydric alcohols, such asdivinyloxyethane and trivinyloxypropane.

As evident from the foregoing, the monomers may be hydrophobic orhydrophilic, or carry other functionality both polar and non-polar,including sites for subsequent attachment of ion exchange functionality.In the case particularly of hydrophobic monomer systems, desiredfunctionality may be provided on the surface of the copolymer by thetechniques described below. However, in all monomer systems of theinvention, the monomers, initiator and liquid suspension medium areselected such that the monomers and initiator are phase separable fromthe medium, and thereby extractable into the pores of the templateparticles. In effect, the monomers and initiator are selected forcompatibility with the template particles and incompatibility(insolubility or diminished solubility) with the liquid suspensionmedium, in order to facilitate good extraction of monomers and initiatorinto the pores of the template particles for polymerization therein.

Generally, phase separation requires that the liquid medium for thepolymerization be aqueous in the case of hydrophobic monomers andnon-aqueous in the case of hydrophilic monomers. However, some water maybe present in the polymerization reaction mixture when one or more ofthe monomers are hydrophilic, provided the hydrated hydrophilic monomersare only slightly soluble in the reaction medium.

Most free radical initiators useful for suspension or emulsionpolymerization (subject to the limitation that both the monomers and theinitiator are phase separable from the liquid reaction medium) may beemployed, including both the peroxy and azo types. Suitable initiatorsare the organic peroxides such as benzoyl peroxide, peroxyesters such ast-butyl peroxybenzoate and the various t-amyl peroxyesters, and dicumylperoxide. Azo initiators include azo-bis-isobutyronitrile. The amount ofinitiator is readily selected by one skilled in the art, and istypically about 0.1-2.0%, based on the weight of the monomers.

Typically, non-aqueous liquid reaction media include various inertorganic solvents such as halogen substituted hydrocarbons, aliphatic andaromatic hydrocarbons. Representative hydrocarbons include isooctane,toluene, ethylene chloride and chloroform.

The template particles for preparing the particulate resins of theinvention generally are porous, inorganic materials such as silica gel,silica, alumina, zirconia, minerals or refractory materials such asglassy substances, and the various metal oxides. Silica gels arepreferred because they are available in a wide variety of forms havinguniform characteristics including particle size, surface area andporosity.

The template particles may, if not inherently compatible, be modified ortreated to provide the requisite compatibility with themonomer/initiator reaction mixture for effective extraction into thepores of the template material. For example, if the monomer system isessentially hydrophobic, and silica gel is the template material, thesilica gel may be treated with a reagent capable of rendering ithydrophobic. Techniques for effecting this transformation are known, andinclude the use of silanizing agents such as trimethyl chlorosilane,hexamethyldisilazane and other dimethylalkylchlorosilanes in which thealkyl substituent may contain from one to about eighteen carbon atoms,preferably about one to four carbon atoms. Treatment with higher alkylhomologs of the silanizing reagent may leave residues and create a needfor more extensive extractions of the polymeric product.

The foregoing techniques for converting a hydrophilic silica gel surfaceto a hydrophobic surface are described in Iler, The Chemistry of Silica,pages 680-702, incorporated herein by reference. A silanizing agent maybe represented by the formula X_(m) Si(R)_(n) R'₄₋(m+n) wherein R may bealkyl or aryl, R' is an alkyl, usually methyl or ethyl, the sum of m andn is not greater than 4, and X is a replaceable group such as Cl, OCH₃,OC₂,H₅, NR₂, NHCOR or the like. Alkyl in the foregoing formula maycontain 1-18 or more carbon atoms, more usually 1-4 carbons atoms, andaryl may contain 6-18 carbon atoms and includes alkaryl groups oraralkyl groups such as tolyl and benzyl.

Other techniques may also be used to convert the hydrophilic silica gelsurface to a hydrophobic surface, such as heating the silica gel with analcohol (ROH) to convert the surface silanol groups to Si--O--R groups,and the adsorption of certain surfactants such as a surfactant based pm(CH₃)₃ ⁺ N(CH₂)_(n) CH₃ and the like.

In preparing the resins of the invention, a reaction mixture is formedof the unsaturated monomers, polyethylenically unsaturated monomers andpolymerization initiator in a liquid state where the volume of thereaction mixture approximately equals the pore volume of the templateparticles. To this mixture the template particles are added withsuitable agitation. This contact results in extraction of the monomersand initiator into the pores of the template particles without undueagglomeration. The kinetics of the extraction will depend primarily uponthe nature of the reaction mixture, liquid medium and templateparticles.

In some cases, enhancement of the extraction can be achieved,particularly in the case of polar monomers such as vinyl acetate, byaddition of a salt to the aqueous suspension medium.

In the case of monomers with a polyether type backbone, these monomersbeing soluble in organic solvents when anhydrous, addition of a smallamount of water to the reaction mixture will cause the monomers toseparate and to improve the extraction of the monomers into ahydrophilic template material. Generally, therefore, the addition ofsmall amounts of water will improve the extraction of hydrophilicmonomers into a hydrophilic template material when the liquid mediumcomprises a nonpolar suspending solvent.

While the addition of a volume of reaction mixture approximately equalto the pore volume of the template particles is useful for avoidingsubstantial agglomeration of the polymerizate, agglomeration can also beminimized by the use of monomers that form water wettable polymers andby the use of additives which will adsorb to the interface oforganic/water systems but preferably will not form micelles. A typicalreagent of this type is butyl sulfonate.

After extraction of the reaction mixture into the pores of the templateparticles, the mixture is heated to a temperature which activates theinitiator present in the reaction mixture, in order to effect thepolymerization and crosslinking. In some cases, as where alow-temperature initiator is used, it may be desirable to re-treat themixture of reactive monomers and template particles with ahigher-temperature initiator, and heat the mixture to the activatingtemperature of that initiator. This will significantly improve therigidity of the resin particles in many cases.

Upon completion of the polymerization reaction, the template matrix isremoved from the crosslinked copolymer, normally by dissolution of thetemplate material. If the template material is silica, contact with anaqueous alkaline solution will effectively dissolve the silica. Analkaline solution having a pH of at least 12 is particularly effectiveto remove silica but lower alkalinity will be effective dependent upontreatment time and temperature.

Aqueous hydrogen fluoride solutions are also effective in removingsilica, alumina and other inorganic template materials, and thisapproach is particularly effective when the template material has beenmodified, as by the various silanization techniques described above.

After removal of the template material, the particulate resin productmay be filtered and washed with water, usually to neutrality, treatedwith a water soluble alcohol such as methanol, and dried. The isolatedcopolymer particles will generally mirror the size, surface area andporosity of the template particles.

If the template particles comprise silica gel, a wide range of surfaceareas, pore volumes and densities can be produced in the resinparticles. In particular, by using silicas that have a more uniform porestructure, the properties of the templated resin become morepredictable. It is thus possible to calculate an expected surface area,pore volume, size distribution and other properties from characteristicsof a template material. For example, surface area can be calculated fromthe formula ##EQU1## where S_(r) and S_(s) are the surface areas of theresin product and the silica, respectively, V_(g) is the pore volume pergram of silica, which is equal to the volume of monomers used, and d_(m)is the density of the monomer mixture. Moreover, since the pore matrixof the template material becomes the resin matrix and vice versa, thetemplate matrix forms the resin pore structure. A measurement of thepore volume and matrix volume of the template material and the densityof the monomers mixture used will enable calculation of the expectedpore volume per unit weight of the resin product. In cases wherepolymerization is associated with a volume decrease from the monomericmixture, larger pores than calculated are obtained. The polymer obtainedfrom Series 82 silica, using the procedure of Example 2 below, gavelarger pores than expected, as indicated by its exclusion separationproperties (See FIG. 2), while the packing of Example 12 below gaveapproximately the expected pore size distribution (See Table 2 undernote g). The pyridyl pendant groups of Example 12 adsorb to the templatesurface and reduce bulk shrinkage. If the polymerization conditions aresuch that micropores are formed in the resin product, the resultingresin surface area will be greater than calculated. However, if a silicatemplate is used which has a large fraction of micropores, the surfacearea of the resin product may be less than calculated because theenclaved polymer smoothes over some of the microporosity or roughness ofthe template surface. Agglomeration of the resin product during thepolymerization can be further minimized by addition of a protectivecolloid such as polyvinyl alcohol or other equivalent materials.

Apart from the use of monomers having desired functionality,functionality can be imparted to the resin particles in various otherways, generally characterized by modification of one or both of thetemplate particle surface and the copolymer resin surface. In a firsttechnique, an ethylenically unsaturated compound carrying the additionaldesired functionality is adsorbed onto the surface of the templateparticles. The desired functionality is then imparted to the copolymerprepared in the template particles by bonding the compound carrying itto the copolymer surface during polymerization, followed by removal ofthe template material. This technique is illustrated in Examples 12 and19 below.

In a second technique, the surface of the copolymer particles isfunctionalized by adding to the polymerizable reaction mixture acompound carrying the desired functionality. The template particles arepreviously modified with complementary functional groups capable ofassociating with the functionality of the added compound. The functionalgroups of the added compound are then populated on the surface of thecopolymer particles during the polymerization and thereafter. Thisprocess is illustrated in Examples 20 and 22 below.

In a third technique, the surface of the copolymer is functionalized bychemically bonding a compound containing the desired functionality ontothe template particles. This functionality is then transferred to thecopolymer during polymerization and removal of the template material.This technique is illustrated in Example 21 below.

The functionality to be imparted to the copolymer by any of theforegoing techniques can be polar or nonpolar, or can be of a typeproviding a site for subsequent ion exchange functionalization. Forexample, providing a chloromethyl group on the copolymer allowssubsequent treatment with amines to form anion exchange resins.Alternatively, a strongly basic anion exchange resin can be produced byselecting, for the polymerization in the template particles, a monomerhaving a tertiary amine group, the resulting groups in the copolymerthen being quarternized with an alkyl halide. Of course, if the aminogroups incorporated into the copolymer are primary or secondary, theresulting ion exchange resin will be weakly basic.

Strongly acidic cation exchange resins may be produced by treating thecrosslinked copolymer with concentrated sulfuric acid. Weakly acidiccation exchange resins may be produced by hydrolyzing a crosslinked,acrylic-ester version of the templated resin particles with an alkalimetal hydroxide solution, to form carboxylic acid groups.

Generally, the particle size, porosity and surface area obtained willdetermine the applications for the resin particles of the invention, andthese characteristics can be predetermined by selection of the templateparticles. Accordingly, the invention provides an efficient andeconomical method of producing uniform, substantially nonagglomeratedcopolymer particles having a wide variety of industrial and other uses.

The following examples further illustrate the invention. Unlessotherwise indicated, all parts and percentages are by weight,temperatures are in degrees Celsius and reagents are of good commercialquality.

DESCRIPTION OF FIGURES

FIG. 1 shows scanning electron micrographs of the template resin and thesilica gel template. FIG. 1A shows the resin prepared following Example2; Series 82 (Supelco, Inc.) silica gel was used as the templatematerial. FIG. 1B shows the Series 82 silica template. This template isa spherical, 5-um, porous silica gel. The similarity of the imprintedresin can be observed in the details of the exterior surface. FIG. 1demonstrates the resemblance between the shape and size of the silicaand its templating resin where even much of the exterior details arepreserve.

FIG. 2 shows two size-exclusion chromatographic (SEC) separations of apolystyrene mixture. For Figure 2A, column packed with the templatematerials, silica gel of Series 82 (Supelco, Inc.) was used, and forFIG. 2B a column packed with a styrene 40% divinylbenzene resin,prepared using the same silica as the template material followingExample 2 was used. Peaks 1-6 are polystyrenes having molecular weightsof 4480, 450, 50, 17.5, 4, and 0.89×10³ dalton, respectively. Peak 7 istoluene. The columns are 15 cm long and 4.6 mm in internal diameter. Themobile phase is dichloromethane and the flow rate is 0.5 ml/min. Thepolymeric particles, when slurry packed at 5000 psi into a stainlesssteel tube are compressed with a loss of about 30% of the inter-particlevolume, compared to the non-compressible silica gel column, whichpermits more polymeric particles to be forced into the same columnspace, providing a larger pore volume for SEC separations. This isevidenced by the larger resolution factors between bands of similarmolecular sizes for the resin versus its template silica column. In thiscase, however, the resin and the silica show similar pore sizedistributions as indicated by a similar separation pattern.

FIG. 3 is a chromatogram of acetaminophen (8), N,N-dimethylaniline (10),nitrobenzene (11), and an impurity (9) in compound 10, separated on acolumn packed with the resin of Example 12 below. The column is 15 cmlong and 4.6 mm in internal diameter. The mobile phase is 35%acetonitrile 65% 0.1M KH₂ PO₄, pH =3.85 and the flow rate is 1.0 ml/min.at ambient temperature. Under these conditions the chromatographicseparation is of a type known as reversed phase chromatography, whichillustrates a different kind of separation mechanism used in FIG. 2.

EXAMPLES PREPARATION OF HYDROPHOBIC SILICA GELS BY SILANIZATION

(A) C₄ - SILICA GEL

Twenty grams of Davisil 641 silica gel (W. R. Grace Co., Baltimore, MD--irregular particles with particle size 16-20 um; mean pore size 150A;distribution 40-300A; pore volume 1.10 ml/g; surface area 290 m² /g;density 0.41 g/ml) were introduced to a 250 ml bottle, and the bottlewas evacuated in an oven while gradually increasing the temperature to150° C., which temperature was maintained for 4 hours. The bottle wasremoved from the oven and cooled down to room temperature in a drydesiccator. To the silica 100 ml of dry toluene, 6.54 g (47 mmol)n-butyldimethylchlorosilane, and 8 ml of dry pyridine were added. Thebottle was closed, shaken to mix and toppled top-to-bottom for 5 hours.The resulting slurry was filtered, washed thoroughly with toluene,methyl chloride and methanol. While filtering and washing, an excess ofsolvent was maintained in the bed to prevent drying and channeling. Thematerial was then oven-dried at 60° C. overnight.

(B) C₁ - SILICA GEL

The preparation of (A) above was repeated in all essential respects,using 5.0 g trimethylchlorosilane in place of then-butyldimethylchlorosilane.

(C) C₂ - SILICA GEL WITHOUT PYRIDINE

The preparation of (A) above was repeated in all essential respects,using 5.0 g of hexamethyldisilazane in place of then-butyldimethylchlorosilane and pyridine.

EXAMPLE 1

To a 500 ml Parr bottle, 10 grams of C₄ -silica gel (prepared as in (A)above) and 100 ml of distilled water were added. The mixture was aeratedwith nitrogen gas for 15 minutes and 10 ml of a mixture of 49:49:2styrene: 80% pure divinylbenzene (DVB): t-butyl peroxybenzoate, freshlyprepared by passing through a butylcatechol remover (Scientific Polymer,Ontario, NY), was added. The mixture was shaken vigorously for 4 hoursat room temperature on a Parr instrument. 150 ml of 0.75% polyvinylalcohol (MW 1000 dalton) was added, and the mixture was shaken foranother 4 hours. While shaking for 24 hours, the suspension was heatedto 120° C. The suspension was then cooled to room temperature, filteredand washed with 100 ml water followed by 50 ml methanol. The precipitatewas added to 500 ml of 3N sodium hydroxide in 40% aqueous methanol andshaken to 14 hours at room temperature to dissolve the C₄ silica gel.The product beads were filtered, washed with water to neutrality, washedwith 100 ml methanol, and oven-dried at 60° C. The properties of thetemplated resin product as compared with the templating silica(silanized silica gel) are given in Table 1 below.

                                      TABLE I                                     __________________________________________________________________________    Properties of the Silicas Used As Templates and the BET                       Surface Areas Measured for the Resins, including Examples 1-20                        SILICA TEMPLATE         TEMPLATED RESIN PRODUCT                                     Average                                Surface Area                     Pore Vol.                                                                           Pore Size                                                                            Surface    Silanized                                                                          Monomers &      (m.sup.2 /gr)                    (gr/ml)                                                                             Angstrom                                                                             (m.sup.2 gr)                                                                       Example                                                                             Silica                                                                             Initiator.sup.a Measured                                                                            Calc               __________________________________________________________________________    Series  0.45  110    145  --    C.sub.4 --                                                                         ST/DVB/67       369   378                82(550).sup.b                        61.5:36.5:2                                                              C.sub.4 --                                                                         ST/DVB/67       419                                                           49:49:2                                  Series  0.48  110    125  --    C.sub.4 --                                                                         ST/DVB/67       430   331                82(750).sup.b                        49:49:2                                  Hypersil.sup.c                                                                        0.61  100    160   2    C.sub.4 --                                                                         ST/DVB/TBPB     431   296                                                     49:49:2                                                             7    C.sub.4                                                                            PTMA/DVB/TBPB   515                                                           49:49:2                                                             12.sup.g                                                                           C.sub.1 --                                                                         VPy/ST/DVB/TBPB                                                               12.6:42.6:42.6:2                                                                              433                      Davisil 641.sup.d                                                                     1.10  150    290  --    C.sub.4 --                                                                         ST/DVB/TBPB     218   416                                                     73.3:24.7:2                                                        --    C.sub.4 --                                                                         ST/DVB/TBPB     375                                                           61.5:36.5:2                                                         1    C.sub.4 --                                                                         ST/DVB/TBPB     473                                                           49:49:2                                                             5    C.sub.4 --                                                                         CMST/DVB/88     351                                                           49:49:2                                                             6    C.sub.4 --                                                                         PTMA/DVB/TBPB   538                                                           49:49:2                                                            10    C.sub.4 --                                                                         VAC/TAIC/TBPB                                                                 49:49:2         326                      Series 100.sup.e                                                                      0.49   75    210   3    C.sub.4 --                                                                         ST/DVB/TBPB     415   466                                                     49:49:2                                                             8    C.sub.4 --                                                                         PTMA/DVB/TBPB   480                                                           49:49:2                                                            13    C.sub.1 --                                                                         ST/DVB/TBPB     469                                                           49:49:2                                                            14    C.sub.1 --                                                                         CMST/DVB/67     332                                                           49:49:2                                                            15    C.sub.1 --                                                                         PTMA/DVB/TBPB   508                                                           49:49:2                                                            16    C.sub.4 --                                                                         PTMA/EGDMA/TBPB 242                                                           58.8:39.2:1.96                                                     17    C.sub.4 --                                                                         DVB/GCMA/TBPB   --                                                            39.2:58.8:1.96                                                     18    NO   PTMA/EGDMA/86   174                                                           49:49:2                                                            19    NO   DDAH/EGDMA/PTMA/86                                                                            255                                                           17:40.5:40.5:2                           Series 100H.sup.f                                                                     0.59  400     35   4    C.sub.4 --                                                                         ST/DVB/TBPB     110    66                                                     49:49:2                                                             9    C.sub.4 --                                                                         CMST/DVB/67     164                                                           49:49:2                                                            11    C.sub.4 --                                                                         VPr/TAIC/TBPB   175                                                           49:49:2                                  __________________________________________________________________________    .sup.a For VAZO 67 (E. I. duPont de Nemours, Wilmington, DE) and VA-86        (Wako Pure Chemical Industries, Tokyo, Japan) polymerization                  was performed at 85° C./24 hrs; and at 120° C./24 hrs for       t-butyl peroxybenzoate. For VAZO 88 (E. I. duPont) it was performed at        100° C./24 hours.                                                      ST: Styrene                                                                   DVB: Divinyl benzene (80% purity)                                             PTMA: Pentaerythritol trimethacrylate                                         CMST: Chloromethyl styrene                                                    VAc: Vinyl acetate                                                            VPr: Vinyl propionate                                                         VPy: 4-Vinyl pyridine                                                         EGDMA: Ethylene glycol dimethacrylate                                         DDHA: 62% Aqueous diallyldimethyl-ammonium hydroxide                          GCMA: Glycidyl methacrylate                                                   FX-14: N-2-(N-ethylperfluoroocatne-sulfonamido)ethyl methacrylate (3M         Industrial Chemical Products Division, St. Paul, MN)                          TAIC: Triallyl isocyanurate                                                   AC: Acrylate                                                                  TBPB: Tert-butyl peroxybenzoate                                               67: vazo 67: 2,2'-Azobis(isobutyronitrile)                                    88: vazo 88: 1,1'-Azobis(cyclohexanecarbonitrile)                             86: VA-86: 2,2'-Azobis(2-methyl-N-(2-hydroxyethyl)propionamide                .sup.b Series 82 (Supleco, Inc., Bellefonte, PA) experimental product,        spherical, 5 micron particles. A 0.4 ml of monomers per 1 gr silica was       used in the templating polymerization.                                        .sup.c Hypersil (Shandon Souther Products Ltd., Chesire, UK) spherical, 5     micron particles. A 0.6 ml of monomers per 1 g silica was used in the         templating polymerization.                                                    .sup.d Davisil 641 (W. R. Grace, Baltimore, MD) irregular, 16-20 micron       particles. A 1.0 ml of monomers per 1 g silica was used in the                templating polymerization.                                                    .sup.e Series 100 (Supleco, Inc., Bellefonte, PA) experimental product,       spherical, 5 micron particles. A 0.50 ml of monomers per 1 g silica was       used in the templating polymerization.                                        .sup.g The pore size (volume) distribution of polymer:                        pore diameter                                                                        pore volume                                                            (Angstrom)                                                                           (ml/g)                                                                 <60    0.005                                                                  60-80  0.516                                                                  80-100 0.309                                                                  >100   0.086                                                                  __________________________________________________________________________

EXAMPLE 2

Example 1 was repeated in all essential respects except for substitutionof Hypersil silica gel (Shandon Southern Products, Ltd., Cheshire,England) in preparation of the C₄ silica gel and used 10 g of the C₄silica gel material and 6.0 ml monomers/initiator mixture. Theproperties of the templated resin product as compared with the templateresin (silanized silica gel) are set forth in Table II below. Samples ofthese resins were heated at conditions under which their organicmaterial burns off to leave an ash residue of their inorganic content.Table 11 summarizes results for resins prepared according to the presentexample, with different conditions for the C₄ -silica digestion. Theresults confirm that complete removal of the silica gel takes placeunder at least two of these conditions, leaving no inorganic ash.

                  TABLE II                                                        ______________________________________                                        ANALYSIS OF RESIDUAL INORGANIC                                                MATERIAL IN CO-POLYMER                                                                                % Weight Loss                                                     Hydrolysis  After                                                 Example.sup.(a)                                                                           Method      550° C./4 hrs                                  ______________________________________                                        2           30% aq. MeOH                                                                              99.5 ± 0.05                                                    3N NaOH                                                                       24 hrs/RT                                                         2           30% aq. MeOH                                                                              98.6                                                              3N NaOH                                                                       6 hrs/60° C.                                               2           70% aq. HF  99.9                                                              24 hrs/RT                                                         ______________________________________                                         .sup.(a) A 0.75-0.95 g sample of Example 2 from a 5 um templated C.sub.4      --Hypersil was used for ash residue determination.                       

EXAMPLE 3

Example 1 was repeated in all essential respects except for substitutionof Series-100 silica gel (Supelco, Inc.) in preparation of the C₄ -silica gel, and use of 10 g of the C₄ - silica gel material and 5.0 mlmonomers/initiator mixture. The properties of the templated resinproduct as compared with the templating silica (silanized silica gel)are set forth in Table I above.

EXAMPLE 4

Example 1 was repeated in all essential respects except for substitutionof Series 100 H silica gel (Supelco, Inc.) in preparation of the C₄ -silica gel, and use of 10 g of the C₄ silica gel material and 5.8 ml ofmonomers/initiator mixture. The properties of the templated resinproduct as compared with the templating silica (silanized silica gel)are set forth in Table I above.

EXAMPLE 5

Example 1 was repeated in all essential respects except for substitutionof 49:49:2 of chloromethylstyrene: divinylbenzene: 1,1'-Azobis(cyclohexanecarbonitrile) for the monomers/initiator mixture of Example1 and heating to 85° C. instead of 120° C. The properties of thetemplated resin product as compared with the templating silica(silanized silica gel) are set forth in Table 1 above.

EXAMPLE 6

Example 1 was repeated in all essential respects except for substitutionof 49:49:2 pentaerythritoltrimethacrylate: divinylbenzene: tert-butylperoxybenzoate for the monomers/initiator mixture of Example 1. Theproperties of the templated resin product as compared with thetemplating silica (silanized silica gel) are set forth in Table I above.

EXAMPLE 7

Example 2 was repeated in all essential respects except for substitutionof the monomers/initiator mixture of Example 6 for the comparablematerials of Example 2. The properties of the templated resin product ascompared with the templating silica (silanized silica gel) are set forthin Table I above.

EXAMPLE 8

Example 3 was repeated in all essential respects except for substitutionof the monomers/initiator mixture of Example 6 for the comparablematerials of Example 3. The properties of the templated resin product ascompared with the templating silica (silanized silica gel) are set forthin Table I above.

EXAMPLE 9

Example 4 was repeated in all essential respects except for substitutionof the monomers/initiator mixture of Example 5 for the comparablematerials of Example 1. The properties of the templated resin product ascompared with the templating silica (silanized silica gel) are set forthin Table I above.

EXAMPLE 10

Example 1 was repeated in all essential respects except for substitutionof 25% NaCl aqueous solution (suspending solvent) for the water and the0.75% polyvinyl alcohol solution of Example 1. The monomer/initiatormixture was a solution of 49:49:2 vinyl acetate: triallyl isocyanurate:tert-butyl peroxybenzoate. The properties of the templated resin productas compared with the templating silica (silanized silica gel) are setforth in Table I above.

EXAMPLE 11

Example 4 was repeated in all essential respects except for substitutionof 49:49:2 vinyl propionate: triallyl isocyanurate: tert-butylperoxybenzoate for the comparable materials of Example 4. The propertiesof the templated resin product as compared with the templating silica(silanized silica gel) are set forth in Table I above.

EXAMPLE 12

Example 2 was repeated in all essential respects except for substitutionof 12.6:42.6:42.6:2 4-vinylpyridine: styrene: divinylbenzene: tert-butylperoxybenzoate for the monomers and initiator of Example 2. After thepolymerization, the silica gel was removed by dispersion of the productin 50 ml 70% aqueous HF solution instead of the 3N sodium hydroxide,followed by filtration, water washing to neutrality, 3N sodium hydroxidetreatment, and with water washing again to neutrality. The properties ofthe templated resin product as compared with the templating silica(silanized silica gel) are set forth in Table I above.

EXAMPLE 13

Example 3 was repeated in all essential respects except for substitutionof 10 grams of the C₁ -Series 100 silica gel and use of 5.0 ml of themonomer-initiator mixture. The properties of the templated resin productas compared with the templating silica (silanized silica gel) are setforth in Table I above.

EXAMPLE 14

Example 5 was repeated in all essential respects except for substitutionof 10 g of the C₁ -Series 100 silica gel and 5.0 ml of themonomer-initiator mixture. The properties of the templated resin productas compared with the templating silica (silanized silica gel) are setforth in Table I above.

EXAMPLE 15

Example 6 was repeated in all essential respects except for substitutionof 10 g of the C₁ -Series 100 silica gel and 5.0 ml of themonomer-initiator mixture. The properties of the templated resin productas compared with the templating silica (silanized silica gel) are setforth in Table I above.

EXAMPLE 16

Example 3 was repeated in all essential respects except for substitutionof 58.8:39.2:1.96 pentaerythritol trimethacrylate: ethylene glycoldimethacrylate: tert-butyl peroxybenzoate for the comparable materialsof Example 3. The properties of the templated resin product as comparedwith the templating silica (silanized silica gel) are set forth in TableI above.

EXAMPLE 17

Example 3 was repeated in all essential respects except for substitutionof 58.8:39.2:1.96 glycidyl methacrylate: divinylbenzene: tert-butylperoxybenzoate for the comparable materials of Example 3. The propertiesof the templated resin product as compared with the templating silica(silanized silica gel) are set forth in Table I above.

EXAMPLE 18

To a 500 ml Parr bottle were added 10 g of Series 100 silica gel(Supelco, Inc.) and 200 ml of isooctane. The mixture was aerated withnitrogen gas for 15 minutes and 5 ml of a mixture of 5.0 g of ethyleneglycol dimethacrylate containing 5% water, 5.0 g penterythritoltrimethacrylate and 0.2 g of VA-86 initiator(2,2-Azobis(2-methyl-N-(2-hydroxyethyl)propionamide) from Wako PureChemical Industries, Ltd.) was added. The mixture was shaken vigorouslyfor 18 hours. Then, while shaking, the suspension was heated to 85° C.for 6 hours, followed by 100° C. for 18 hours. The mixture was thencooled to room temperature, filtered, and the precipitate washed withtoluene, methylene chloride, methanol and water. The precipitate wasadded to 500 ml of 3N sodium hydroxide in 40% aqueous methanol andshaken for 24 hours at room temperature to dissolve the silica gel. Theproduct beads were filtered, washed with water to neutrality, washedwith 100 ml methanol, and oven-dried at 60° C. The properties of thetemplated resin product as compared with the templating silica(silanized silica gel) are set forth in Table I above.

EXAMPLE 19

Example 18 was repeated in all essential respects except forsubstitution of 17:40.5:40.5:2 62% aqueous diallyldimethylammoniumhydroxide: ethylene glycol dimethacrylate: pentaerythritoltrimethacrylate: VA-86 initiator for the monomers/initiator mixture. Theproperties of the templated resin product as compared with thetemplating silica (silanized silica gel) are set forth in Table I above.

EXAMPLE 20 Step 1 Preparation of modified diol-CF Silica Gel

To 15 g of Supelcosil LC-diol (a silica gel surface-modified with asilane-bonded alkoxy alkanediol, from Supelco, Inc.) placed in a 250 mlbottle was added 50 ml of pyridine, 50 ml of methylene chloride, and 2.5g of 4-dimethylaminopyridine and 4.5 g heptafluorobutyryl chloride. Thebottle was closed and shaken for 12 hours. The slurry was filtered,washed thoroughly with acetone, methanol, water and methanol. Thematerial was finally air dried.

Step 2 Preparation of Templated Resin

To a 500 ml Parr bottle was added 11.2 g of the modified silica diol-CFof step 1 and 150 ml of distilled water. The mixture was aerated withnitrogen gas for 15 minutes, and 5 ml of a 23.7:29.8:44.6:1.9 FX-14:pentaerythritol trimethacrylate: divinylbenzene: tert-butylperoxybenzoate mixture was added. The mixture was shaken vigorously on aParr instrument for hours and 150 ml of 0.75% aqueous polyvinyl alcoholwas added while the shaking was continued for another 14 hours. Thenwhile shaking, the suspension was heated and held at 120° C. for 24hours. The mixture was cooled to room temperature, filtered, and theprecipitate was washed with toluene, methylene chloride, methanol andwater. The precipitate was added to 500 ml of 3N sodium hydroxide in 40%aqueous methanol and shaken for 24 hours at room temperature to dissolvethe silica gel. The product beads were filtered, washed with water toneutrality, followed by washing with 100 ml methanol, and air-dried atroom temperature. (FX-14 is N-2-(N-ethylperfluorooctanesulfonamide)ethylmethacrylate from 3M Company, St. Paul, MN.)

EXAMPLE 21 Step 1 Preparation of hydroxyl bonded silica gel

To 20 g of Series 100 silica gel (Supelco, Inc.) was added 6.80 g of a62% alcoholic solution ofN,N-bis(2-hydroxyethyl)-3-aminopropyltriethoxysilane and 250 ml oftoluene. The mixture was refluxed and 50 ml of the first distillationwas azeotropically removed, followed by 5 hours of reflux. The mixturewas filtered and thoroughly washed with toluene, methylene chloride, andmethanol. The white product was oven-dried at 60° C. under nitrogen.

Step 2 Preparation of modified diol-AC

Example 20, Step 1 was repeated in all essential respects using acryloylchloride (AC) in place of the heptafluorobutyryl chloride (CF) and theproduct of Step 1 of this Example 21 in place of Supelcosil LC-diol.

Step 3 Preparation of Templated Resin

Example 18 was repeated in all essential respects except forsubstitution of the modified diol-AC of Step 2 above for the silica gelof Example 18.

EXAMPLE 22

10g of Supelcosil LC-SAX (a silica gel surface-modified withsilane-bonded quaternary ammonium functionality, from Supelco, Inc.), astrong anion exchanger, was suspended in 20 ml of water containing 3.5 gsodium sulfonated styrene for 30 minutes. The mixture was filtered andwashed with water and methanol. The silica was dried under vacuum andsuspended in 200 ml water containing 5.3 ml of 49:49:2 styrene: DVB:tert-butyl peroxybenzoate. The polymerization and the following stepswhere according to Example 20.

We claim:
 1. A porous, rigid resin comprising particles of crosslinkedcopolymer derived from monoethylenically unsaturated monomers andpolyethylenically unsaturated crosslinking monomers, said copolymerresulting from polymerization, in the pores of porous inorganic templateparticles, of a reaction mixture comprising said monomers and apolymerization initiator in a liquid medium in which the monomers andinitiator are phase separable and extractable therefrom into the poresof the template particles, followed by removal of the template particleswithout destruction of the copolymer, whereby the isolated copolymermirrors the size, surface area and porosity of the template particles.2. The resin of claim 1 wherein the template particles are selected froma porous silica gel, alumina, zirconia, a mineral, and a refractorymaterial.
 3. The resin of claim 1 wherein the monomers, the initiatorand the template particles are hydrophobic, and the reaction mixturecomprises an aqueous medium.
 4. The resin of claim 1 wherein themonomers, the initiator and the template particles are hydrophilic, andthe reaction mixture comprises a hydrophobic suspending medium.
 5. Theresin of claim 3 wherein the template particles comprise silanizedsilica gel particles and the reaction medium is aqueous.
 6. The resin ofclaim 5 wherein the silanization is effected with a trialkyl (C₁ -C₁₈)halosilane.
 7. The resin of claim 5 wherein the silica gel has anaverage pore size from about 3 to about 2000 nm, a porosity of at least30% and a surface area from about 5 to about 1000 m² /g.
 8. The resin ofclaim 1 wherein the copolymer carries polar functionality.
 9. The resinof claim 8 where in the polar functionality is cationic.
 10. Thetemplated resin of claim 9 wherein the cationic functionality comprisespyridinyl groups.
 11. The resin of claim 8 wherein the polarfunctionality is anionic.
 12. The resin of claim 1 wherein themonoethylenically unsaturated monomers are selected from aromaticmonomers, acrylic monomers, or mixtures of aromatic and acrylicmonomers.
 13. The resin of claim 1 wherein the copolymer is a styreniccopolymer.
 14. The resin of claim 1 wherein the styrenic copolymer is acopolymer of styrene and divinylbenzene.
 15. The resin of claim 1wherein the copolymer is an acrylic copolymer.
 16. The resin of claim 1wherein the acrylic copolymer is copolymer of divinylbenzene and analkyl (C₁ -C₈) acrylate of methacrylate.